31.8mm of durable control

Run your favorite 31.8mm clamping diameter handlebar on a bike with Knock Block with the Rhythm Comp 31.8. It adds Knock Block compatibility to a durable stem with multiple lengths to let you fine-tune the fit to your ride.

Product details

Get 31.8mm handlebar compatibility with your Knock Block system

Also compatible with standard headsets and spacers

Knock Block system protects frame from impacts by fork and handlebars by eliminating over-rotation of bars

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